Get a glimpse of NYC's rarely seen spaces—from boardrooms to bedrooms, crypts to clubs, factories to firehouses, lighthouses to lookouts, monuments to mansions, skyscrapers to substations—with Open House New York, an event that will satisfy anyone's inner snoop. Past tour spots have included the Four Seasons (the Phillip Johnson–designed restaurant, not the hotel), the Old Croton Aqueduct Trail, the New York Academy of Medicine and even the Newtown Creek Wastewater Treatment Plant. New additions to this year's weekend include City Hall, which recently underwent a complete renovation; the New York City headquarters of Google in Chelsea; the art deco Central Library of the Brooklyn Public Library; and Staten Island’s National Lighthouse Museum. Plus, check out the talks, workshops and OHNY Kids tours. For updates on this year's schedule, and to RSVP for limited-admission events, visit ohny.org.